Refrigeration



Dec. 5, 1939. KUCHER 2,182,153

REFRIGERATION Original lfiled April 28, 1932 3 Sheets-Sheet 2 Dec.-5, 1939. A. A. KUCHER I REFRIGERATION Original Filed April 28, 1932 3 Sheets-Sheet 3 I t V 23 259 1 I Patented Dec. 5, 1939 i UNITED STATES PATENT OFFICE REFRIGERATION Andrew A. Kucher, Dayton, Ohio, assignor, by

mesne assignments, to General Motors Corporation, a corporation of Delaware Application April 28, 1932, Serial No. 608,052

.Renewed September 10, 1938 26 Claims. (Cl. 62-115) This invention relates to refrigeration. modified as shown in Figs. 1 and 2 and diagram- It is among the objects of this invention matically indicated in Figs. 3 and 4. to provide a refrigerating apparatus of the In this construction the evaporator 200 is procontinuously running compressor-condenservided with a relatively large liquid refrigerant 5 evaporator type, such as is described in my reservoir in the ice-making zone capable of holdpending application Serial No. 599,239, filed ing a large reserve supply of liquid refrigerant March 16, 1932, to which reference is hereby of such volume that, when it is transferred to made for a further understanding of this inventhe condenser, the effective condensing area of tion, with improved ice-making capacity. the condenser is materially reduced. When so It is a further object of this invention to proconstructed, the decreased effective condensing 10 vide such an apparatus with a readily accessible area of 'the condenser materially increases the adjustment for selectively varying the refrigeratcondensing pressures above normal operation ing-effect of the system on the object being pressure, and thus causes an increased flow of cooled. Also it is an object of this invention to refrigerant into the evaporator through the rerender a refrigerating apparatus continuously or strictor. The refrigeration capacity of the sys 15 I intermittently running type more adaptable to tem is thus temporarily increased by the intransportation for service or installation. creased refrigerant flow and provides a substan- Further objects and advantages of the present tial increase in the ice freezing capacity of the invention will be apparent from the following system.

description, reference being had to the accom- As shown in Figs. 1 and 5, the evaporator 200 20 panying drawing, wherein a preferred form of is provided with a relatively large liquid rethe present invention is clearly shown. frigerant reservoir, which may conveniently be In the drawings: formed by the ice tray shelves 2M and 202 which Fig. 1 is a vertical cross-sectional view of an enclose the liquid refrigerant spaces 203 and 204 apparatus embodying features of this invention; capable of containing a substantial amount of 25 Fig. 2 is a partial horizontal cross-sectional liquid refrigerant. When this refrigerant is .view taken along the line 2-2 of Fig. 1; transferred to the condenser under abnormal, or Figs. 3 and rare diagrammatic and exagice-making conditions, the liquid refrigerant gerate d views indicating varying ratios of liquid stands in the condenser a certain distance above refrigerant in the evaporator and condenser the normal liquid refrigerant level therein and 30 when the system operates under normal condipreferably the liquid refrigerant capacities are tions when ice is not being made, and under abso corelated in the system that the liquid renormal, or ice making conditions; frigerant rises to the header 205 of the condenser Fig. 5 is a vertical cross-sectional view of a 206 under abnormal, or ice-making, operation.

portion of Fig. 1, taken along the line 55 there- 4 The operation of a system made with this in- 35 i of creased ice freezing capacity is as follows: Under Fig. 6 is an enlarged horizontal cross-sectional normal operation when ice is not being made, the View taken along the line 66 of Fig. 5 compressor 201 which runs continuously at a Fig. 7 shows the compressor-condenserconstant speed without stopping for cabinet tem- 40 evaporator system removed from the cabinet andperature adjustments, in accordance with the 40 rendered compact for transportation; disclosure in my copending application, com- Fig. 8 is a view showing the system removed presses refrigerant and discharges it through the from the cabinet and rendered'compact in an-- line 208 to the condenser 206. Under normal other manner; and crated for transportation; operation, the amount of refrigerantin the sysand p tem is such that liquid refrigerant does not-rise 45 Fig. 9 is a cross-sectional detail of one of the substantially above t e hea o qu d refrigerrefrigerant lines, showing a protective covering ant receiver 209. The liquid refrigerant then to prevent sharp bends. continues through the pipe 2H], to the refrigerant expander 2| I. The expander 2 may be of the Modzficatwn for z-ncreaslgg producing construction shown in*my copending application, 50 capacz or it may be modified as shown in Fig. 6 here- $ometimes it is desirable to increase the ice after to be more fully described The expanded making capacity of the type of system described refrigerant then passes through the pipe 2|2 to in my copending application above referred to, the liquid space 204. Thereafter it passes and for this purpose the construction may be through the pipe 2I3 to the liquid space 203. 5

From thence it continues through the pipe 2M3 to the distributing channel 2H5 from whence it passes around the spot-welds 2% in the outer shell 22| of the evaporator in a manner similar to the operation described in the said application and continues to the heat interchanger 2 l l where it cools the incoming unexpanded liquid refrigerant in pipe 2H0 which connects the condenser 206 with the expander 2i i, from thence it continues through the pipe 2E8 to the compressor and repeats the cycle.

Under normal operation, when ice is not being frozen, the liquid refrigerant in the spaces 203 and 204, being insulated more or less from the air currents in the food compartment are of the cabinet 220, does not evaporate materially beyond the requirements for removing the specific heat of the condenser liquid, and the construction is such that the unevaporated liquid stands in a relatively quiescent condition in these reservoirs and is discharged or spills over into the distributing channel 2H5 of the air cooling outer shell 22l of the evaporator. Under normal conditions the refrigerant which is absorbing the heatv leak into the cabinet is evaporated suband 223 are inserted into the evaporator with water to be'frozen, and thus create an abnormal operating condition, a large quantity of heat is introduced into-the liquid refrigerant in the spaces 203 and 204 and causes a large quantity of liquid refrigerant to be evaporated. This quickly increases the back pressure in the evaporator, so that the compressor 207, because of its continuous operation, introduces a large quantity of refrigerant into the condenser 206. This refrigerant is quickly condensed, so that an abnormally large quantity of liquid refrigerant is introduced into the condenser faster than it is normally discharged by the expander 2 into the evaporator 200. Under such abnormal conditions, the ratio of liquid refrlgerantin the evaporator and condenser is varied, the liquid refrigerant in the condenser 206 rising above the normal level in an amount sufficient to blanket the effective condensing area and thus increase the normal condensing pressures, as diagrammatically shown in Fig. 4. The header 205 is placed in the condenser at the proper helghth and is of sufiicient, capacityto prevent liquid refrigerant from rising in the condenser above this point. The header 205 thus insures the proper ratio of blanketing in the condenser and removes the necessity of too closely measuring the amount of refrigerant introduced, into the system. The abnormally high condenser pressures produced under ice-making conditions force an increased amount of liquid refrigerant through the expander 2, which in turn pro vides an increased amount of refrigerant to be evaporated-in the evaporator. Under theseconditions the system operates at an increased cae pacity over the normal operation as described in my copending application. As the water turns into ice, the rateof evaporation of refrigerant due to the ice-making factor is reduced, and

gradually the system returns to its normal op eration.

Temperature adjustments for individual requirements When desired, means are provided whereby the user may vary the temperatures maintained by the system in the objectbeing cooled. To this end, convenient means of varying the effective.

charged into the evaporator, this combined length and area being determined in accordance with my copending application. Supplemental passages 232, 233 and 234 may be provided which tap the passage 230 at various points on one or both sides of passage 23d. Any suitable means of establishing a refrigerant flow connection between any of the passages 23L 282, 233 or 236 with the passage 230 may be provided, and for this purpose a Vernier-like valve 235 may be used. This valve conveniently is in the form of a rod having transverse passages 230 to 209 inelusive so arranged that they connect the various passages 23! to 23% inclusive with the passage 230 and with the pipe 2l2, depending on the position of the valve 235 as is apparent from Fig. 6. The valve 235 may be provided with convenient means for manual adjustment. This may include a bellows 2&0 to prevent the flow of refrigerant along the valve or rod 235. A spring 2M urges the valve 235 in one direction as shown in Fig. Sand this, force is counteracted by the manual adjustment device. This device includes the cam-like structure 202 secured to the valve 235 cooperating with the revolvable cam 243 having a ball-and track engagement 244 with the front plate 245 of the evaporator 200. By turning the cam 243 to positions indicated by the pointer 246, various positions of the valve 235 are obtained which vary the effective length of the passage 230. By this means, the individual user of the system can select any one of several lengths of orifice which increase or decrease the capacity of the system and thus provide colder or warmer temperatures in the cabinet. 220 or other object being cooled.

The calibration of the elongated orifice, in accordance with my copending application, is such that the flow through the passages 230 and 23! When the user varies the length of the orifice by turning the cam 243, the effective length is varied slightly, but sufiiciently to vary the temperature of the cabinet. Such adjustment main- Servicing This and similar systems may, if desired, be constructed so as tobe adapted for factory service. Under such conditions it is desirable to construct the compressor, condenser and evaporator as a unitary structure which may be removed from the cabinet without disconnecting the refrigerant connections and may thus be transported to the factory or branch for repair. To this end the condenser 206 is shown as secured to a vertical side of the cabinet 220 by screws or the like 250 which are readily removed. The compressor and evaporator are mounted on a common base 25I which is supported on the cabinet independently of the condenser. The base 25l may form at least part of one of the walls of the cabinet and preferably forms part of the top of the food compartment. The condenser is connected to the compressor and evaporator by flexible lines 208 and 2l0 so that the system may be rendered more compact for' transportation after it is removed from the cabinet. The condenser, together with the evaporator and compressor may be removed with the top 25! of the food compartment. This unitary structure may be shipped in any convenient crate either by bending the pipes 208 and 2!!! so that the condenser assumes the position as shown in Fig. '7, or it may be placed alongside the condenser and evaporator so that it may be shipped in a crate as shown in Fig. 8, and under these conditions, the lines 208 and 2| 0 may have part of their outer surfaces protected by spirally wound wire 252 in order to protect the same from undue kinking during the servicing operation.

The condenser may be provided with means for insuring that it is properly spaced from the wall of the building in which the apparatus is installed, so that an effective circulation of air over the condenser is obtained. Preferably such means are made integral with the condenser. The condenser is made of two metal sheets 260 and 26l welded together along the edges and spot-welded at intermediate points where one of the sheets is indented at 262. Sheets 260 extends beyond sheet 26I and is bent as at 263 to provide abutments which limit the extent to which the cabinet may be moved towards the wall 264 of the building, and thus insures proper air circulation on both sides of the fiat air cooled portion of the condenser which lies between the abutments 263.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understoodthat other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. A refrigerating apparatus consisting of a cabinet, a refrigerafing system therefor of a capacity not substantially in excess of the maximum normal refrigeration requirements of said cabinet, said system comprising a compressorcondenser-evaporator refrigerating system in which the compressor runs continuously at constant speed during the entire period ofrefrigeration requirement without stopping for cabinet refrigeration temperature adjustments, and circulates refrigerant continuously throughout the entire system, a refrigerant expander of normally fixed dimensions between the condenser and evaporator of a size. to vary the effective refrigerating area of the evaporator in response to refrigerant pressure in the evaporator in an amount suificient to maintain the cabinet temperature within food preserving limits notwithstanding variations in the heat leakage through the walls into the cabinet, and means selectively to vary at least one dimension of said expander to produce a different refrigerating effect on the cabinet.

2. A refrigerating apparatus consisting of a cabinet, a refrigerating system therefor of a capacity not substantially in excess of the maximum normal refrigeration requirements of said cabinet, said system comprising a compressorcondenser-evaporator refrigerating system in which the compressor runs continuously at constant speed during the entire period of refrigeration requirement without stopping for cabinet refrigeration temperature adjustments, and circulates refrigerant continuously throughout the entire system, a refrigerant expander of normally fixed dimensions between the condenser and evaporator of a size to vary the refrigerant flow in response to the refrigerant pressures in the evaporator and condenser in an amount suflicient to maintain the cabinet temperature within food preserving limits notwithstanding variations in the heat leakage through the walls into the cabinet, and means selectively to vary at least one dimension of said expander to produce a different refrigerating effect on the cabinet.

3. A refrigerating apparatus comprisi g a household refrigerator cabinet having a food preserving space and an ice-making space, a compressor condenser evaporator refrigerator system assembled with said cabinet, said com pressor operating continuously and circulating refrigerant continuously throughout the system and throughout the normal room temperature range without stopping for cabinet temperature adjustments, said evaporator having a refrigerant evaporating portion in thermal contact with said ice-making space and another evaporating portion in thermal contact with said food preserving space, an elongated orifice between said condenser and said evaporator having a length and cross-sectional area coordinated with the heat leak into the cabinet under varying room temperatures so that the evaporator maintains the cabinet temperature within food preserving limits and the ice-making space below.

32 F. notwithstanding the continuous operation of the compressor and the variations in room temperature, and means to vary the length of said orifice the construction being such that the introduction of water to be frozen into said icemaking space causes an abnormal rise in condenser pressure.

4. A refrigerating apparatus comprising a household refrigerator cabinet having a food preserving space and an ice-making space, a compressor condenser evaporator refrigerator system assembled with said cabinet, said compressor operating continuously and circulating refrigerant continuously throughout the system and throughout the normal room temperature range without stopping for cabinet temperature adjustments, said condenser having an air cooled effective condensing area said evaporator having a refrigerant evaporating portion in thermal contact with said ice-making space and another evaporating portion in thermal contact with said food preserving space, an elongated orifice between said condenser and said evaporator having a length and cross-sectional area coordinated with the heat leak into the cabinet under varying room temperatures so that the evaporator maintains the cabinet temperature within food preserving limits and the ice-making space below 32 F. notwithstanding the continuous operation of the compressor and the variations in room temperature, the construction frozen into said ice-making space causes an abnormal rise of liquid refrigerant in said con-.

ant continuously throughout the system and v the system and throughout the normal room temthroughout the normal room temperature range Without stopping for cabinet temperature adjustments, said evaporator having a refrigerant evaporating portion in thermal contact with said ice-making space and another evaporating portion in thermal contact with said food preserving space, an elongated orifice between said condenser and said evaporator having a length and cross-sectional area coordinated with the heat leak into the cabinet under varying room temperatures so that the evaporator maintains the cabinet temperature within food'preserving limits and the ice-making space below 32 F. notwithstanding the contnuous operation of the compressor and the variations in room temperature, the construction of said condenser being such that the introduction of water to be frozen into said ice-making space causes an abnormal rise of liquid refrigerant in said condenser to reduce materially its effective condensing area, said condenser having a reservoir intermediate its inlet and normal liquid level to limit the abnormal rise of liquid refrigerant.

6. A refrigerating apparatus consisting of a household refrigerator cabinet having a food preserving space and in ice-making space, a compressor-condenser-evaporator refrigerator system assembled with said cabinet, said compressor operating continuously and circulating refrigerant continuously at constant speed throughout perature range without stopping for cabinet temperature adjustments, said evaporator having a relatively long refrigerant passage between its inlet and outlet in thermal contact with the icemaking space and means shielding said ice-making space from the food preserving space of the cabinet, a refrigerant expander having a normally fixed dimension between said condenser and the inlet of said evaporator to vary the effective refrigerating area and refrigerant temperature of said evaporator in an amount suflicient to maintain the cabinet temperature within foo-d preserving limits and-the ice-making space below 32 F., and expander adjustment means for selectively varying the expanding capacity of said expander. I

7. A refrigerating apparatus comprising a domestic refrigerator cabinet having a food preserving space, a compressor-condenser-evaporator refrigerator system assembled with said cabinet, said compressor operating continuously and circulating refrigerant continuously throughout the system during the entire refrigeration requirements of the cabinet without stopping for cabinet temperature adjustments, an evaporator in said cabinet having an ice-making portion including a liquid refrigerant reservoir shielded from said food preserving space, and having a cooling portion in thermal contact with said food preserving space, and an elongated orifice between said condenser and said evaporator having a length and cross-sectional area coordinated withthe heat leak into the cabinet under varying room temperatures so that it varies the evaporator cooling capacity in an amount sufficient to maintain the cabinet food preserving space temperature within food preserving limits notwithstanding the continuous operation of the compressor and the variations in room temperature, the charge of refrigerant in said system being such that when liquid refrigerant is evaporated in said liquid refrigerant reservoir by water introduced in said ice-making portion, the effective condensing area in said condenser is blanketed by a rise in the normal condenser liquid level to increase the flow of refrigerant through said orifice.

8. A refrigerating apparatus comprising a domestic refrigerator cabinet having a food preserving space, a compressor-condenser-evaporator refrigerator system assembled with said cabinet, said compressor operating continuously and circulating refrigerant continuously throughout the system during the entire refrigeration requirements of the cabinet without stopping for cabinet temperature adjustments, an evaporator in said cabinet having an ice-making portion including a liquid refrigerant reservoir shielded from said food preserving space, and having a cooling portion in thermal contact with said food preserving space, and an elongated orifice between said condenser and said evaporator having a length and cross-sectional area coordinated with'the heat leak into the cabinet under varying room temperatures so that it varies the evaporator cooling capacity in an amount sufficient to maintain the cabinet food preserving space temperature within food preserving limits notwithstanding the continuous operation of the compressor and the variations in room temperature, the charge of refrigerant in said system being such that when liquid refrigerant is evaporated in said liquid refrigerant reservoir by water introduced in said ice-making portion the efiective condensing area in said condenser is blanketed by a rise in the normal condenser liquid level to increase the flow of refrigerant through said orifice, said condenser being provided with an intermediate reservoir to prevent a rise-of liquid level in said condenser above said intermediate reser- V011.

9. A refrigerating apparatus consisting of a cabinet, a compressor-condenser-evaporator refrigerating system therefor, said system including a continuously running compressor which circulates refrigerant throughout the entire system continuously at constant speed during the entire period of refrigerationiequirement without stopping for cabinet refrigeration temperature adjustments, a normally fixed elongated orifice of a length dimension and cross-sectional area dimen' sion sufficient to vary the evaporator capacity to maintain the cabinet temperature within food preserving limits notwithstanding variations in temperature of the airsurrounding the cabinet, and means for selectively varying one of said dimensions of said orifice.

10. A refrigerating apparatus comprising a household refrigerator cabinet having a food preserving space and an ice-making space, a compressor condenser fixed restrictor evaporator refrigerator system assembled with said cabinet, said compressor operating continuously and circulatingv refrigerant continuously throughout the system and throughout the normal, room temperature range without stopping for cabinet temperature adjustments, said condenser having a liquid receiver and an effective condensing area varying the capacity of the system throughout the normal room temperature range in an amount sufiicient to produce the required quantity of ice and to maintain the cabinet within the food preserving temperature zone, said condenser being of a construction and said evaporator having a. normal liquid refrigerant content sufficient andeffective to raise the condenser liquid refrigerant level to decrease the effective condensing area and increase the condenser pressure in an amount to increase the normal capacity of the system upon the introduction of maintain said object at the desired temperature,

and modifying the normal circulation of refrigerant in said system upon an abnormal refrigeration demand by abnormally varying the ratio of liquid refrigerant in said evaporator and condenser to decrease the effective condensing area and to increase the condenser pressure and vary the normal flow of refrigerant through said ori- 12. A refrigerating apparatus comprising a cabinet and a compressor-condenser-evaporator system unitarily assembled on said cabinet, said compressor and evaporator being mounted on a base removable from said cabinet, said condenser being removably secured to said cabinet by means other than said base, and flexible refrigerant connections from said condenser to said compressor and evaporator whereby said system may be removed from said cabinet without disconnecting the refrigerant flow connections and may be rendered compact for transportation.

13. A refrigerating apparatus comprising a cabinet and a compressor-condenser-evaporator system unitarily assembled on said cabinet, said compressor and evaporator being mounted on a base removable from said cabinet, and forming at least part of a wall of said cabinet, said condenser being removably secured to a vertical side of said cabinet by means other than said base, and flexible refrigerant connections from said condenser to said compressor and evaporator whereby said system may be removed from said cabinet without disconnecting the refrigerant fiow connections and may be rendered compact for transportation.

14. A refrigerating apparatus comprising a cabinet and a refrigerating system assembled with said cabinet, said system including a condenser mounted on one of the vertical walls of the cabinet, said condenser comprising a fiat vertical air-cooled portion formed of two metal sheets parallel with said vertical wall, one of said sheets having a projection formed by a portion of said sheet for limiting the movement of the cabinet toward a wall of the building in which it is installed to insure air circulating spaces on both sides of said air-cooled portion.

15. A refrigerating apparatus comprising a household refrigerator cabinet having a food preserving space and an ice-making space, a compressor-condenser-evaporator refrigerator sysflow of liquid into said orifice from said con denser under all normal room temperature compressor operating conditions, the construction being such that the introduction of water to be frozen into said ice-making space causes an abnormal rise of liquid refrigerant in said condenser to reduce materially its effective condensing area, and means to limit the rise of liquid in said condenser beyond a predetermined point.

16. A refrigerating apparatus comprising a household refrigerator cabinet having a food preserving space and an ice-making space, a compressor-condenser-evaporator -refrigerator system assembled with said cabinet, said evaporator having a refrigerant evaporating portion in thermal contact with said ice-making space and an evaporating portion in thermal contact with said food preserving space, an elongated orifice between said condenser and said evaporator having a length and cross-sectional area to maintain a flow of liquid into said orifice from said condenser under all normal room temperature compressor operating conditions, the construction being such that the introduction of water to be frozen into said ice-making space causes an abnormal rise of liquid refrigerant in said condenser to reduce materially its effective condensing area, said condenser having a reservoir intermediate its inlet and normal liquid level to limit the abnormal rise of liquid refrigerant.

17. A refrigerating apparatus comprising a domestic refrigerator cabinet having a food preserving space, a compressor-condenser-evaporator refrigerator system assembled with said cabinet, an evaporator in said cabinet having an ice-making portion including a liquid refrigerant reservoir, and having a cooling portion in thermal contact with said food preserving space, and an elongated orifice between said condenser and said evaporator having a length and cross-sectional area to maintain a flow of liquid into said orifice from said condenser under all normal room temperature, compressor operating conditions, the charge of refrigerant in said system being such that when liquid refrigerant is evaporated in said liquid refrigerant reservoir by water introduced in said ice-making portion, the effective condensing area in said condenser is blanketed by a rise in the normal condenser liquid level to increase the flow of refrigerant through said orifice, said condenser being provided with an intermediate reservoir to prevent a rise of liquid level in said condenser above said intermediate reservoir.

18.- A refrigerating apparatus comprising .a household refrigerator cabinet having a food preserving space and an ice-making space, a compressor-condenser-fixed restrictor-evaporator refrigerator system assembled with said cabinet, said compressor operating continuously and circulating refrigerant continuously throughout the system and throughout the normal roomtemperature range without stopping for cabinet temperature adjustments, said condenser having an air cooled effective condensing area, anelongated orifice between said condenser and evaporator, the length and cross-sectional area of said orifice,

the refrigerant content and construction of said said ice-making space, the effective condensing area in said condenser is substantially blanketed by-a rise in the normal condenser liquid level to increase the flow of refrigerant through said orifice. Y

19. A. refrigerating apparatus comprising a household refrigerator cabinet having a food preserving space and an ice-making space, a compressor-condenser-evaporator refrigerator system assembled with said cabinet, said compressor operating continuously and circulating refrigerant continuously throughout the system and throughout the normal room temperature range without stopping for cabinet temperature adjustments, an elongated orifice between said condenser and evaporator, the length and crosssectional area of said orifice, the refrigerant content and construction of said condenser and evaporator being so arranged that upon the introduction of water to be frozen into said icemaking space, the efiective condensing area in said gondenser is blanketed by a rise in the normal condenser liquid level to increase the flow of refrigerant through said orifice, said condenser being provided withan intermediate reservoir of a capacity suiiicient to prevent a rise of liquid level in said condenser above said intermediate reservoir.

20. A refrigerating apparatus comprising a cabinet and a refrigerating system assembled with said cabinet, said system including a condenser mounted on one of the vertical walls of the cabinet, said condenser comprising a flat ,vertical air-cooled portion formed of two metal sheets parallel with said vertical wall, means along the edges of said condenser enclosing the space between said condenser and cabinet wall to form a flue, and means along the edges of said condenser adapted to enclose the space between said condenser and a wall of the building in which it is installed to form a second flue.

21. A refrigerating apparatus comprising a compressor-condenser and evaporator, said condenser comprising a relatively elongated fiat surface and having a normal refrigerant reservoir at the bottom and a second liquid receiver above said first named receiver for limiting the rise of liquid refrigerant in said condenser and a charge of refrigerant in said system suiiicient for the liquid refrigerant to rise above said first named receiver at times during the operation of said system, but insuflicient to rise above said second receiver.

22. The method of refrigerating a food preserving space and a freezing space which c0mprises expanding refrigerant through 'a fixed elongated orifice, discharging the refrigerant so expanded into a reservoir in said freezing space andshielded from the circulation of air in said food space, normally maintaining a, body of liquid refrigerant in said reservoir, overflowing liquid 23. A refrigerating apparatus comprising a) household refrigerator cabinet having a food preserving space and an ice-making space, a closed aieaiss compressor condenser evaporator refrigerator system assembled with said cabinet, said evaporator having a refrigerant evaporating portion in thermal contact with said ice-making space and an evaporating portion in thermal contact with said food preserving space, an elongated orifice between said condenser and said evaporator having a length and cross-sectional area to maintain a flow of liquid into said orifice from said condenser under all normal room temperature compressor operating conditions, the construction being such that the introduction of water to be frozen into said ice-making space causes an abnormal rise of liquid refrigerant in said condenser to reduce materially its effective condensing area, said condenser having a reservoir intermediate its inlet and normal liquid level to limit the abnormal rise of liquid refrigerant.

24;. A refrigerating apparatus comprising a domestic refrigerator cabinet having a food preserving space, a closed compressor-condenserevaporator refrigerator system assembled with said cabinet, an evamrator in said cabinet having an ice-making portion including a liquid refrigerant reservoir, and having a cooling portion in thermal contact with said food preserving space, and an elongated orifice between said condenser and said evaporator having a length and prose-sectional area to maintain a flow of liquid into said orifice from said condenser under all normal room temperature, compressor operating conditions, the charge of refrigerant in said system being such that when liquid refrigerant is evaporated in said liquid refrigerant reservoir by water introduced in said ice-making portion, the effective condensing area in said condenser is blanketed by a rise in the normal condenser liquid level to increase the flow of refrigerant through said orifice, said condenser being provided with an intermediate reservoir to prevent a rise of liquid level in said condenser above said intermediate reservoir. 1

25. A refrigerating apparatus comprising a compressor-condenser and evaporator, said condenser comprising a relatively elongated passageway and having a normal liquid refrigerant discharge at the bottom and a liquid receiver above said discharge and intermediate the lengt of said passageway for limiting the rise of liquid refrigerant in said condenser, and a charge of refrigerant in said system suificient for liquid refrigerant to rise above said discharge opening at times during the operation of said system, but ins cient to rise above said receiver.

26. In a compressor-condenser-expander type refrigerator, the method of maintaining a substantially constant temperature in a cabinet during changes in temperature of the environment air about the cabinet, which method consists in circulating refrigerant through an evaporator which cools the interior of the cabinet and through a condenser which is subject to the said environment air, increasing and decreasing the contact surface between liquid refrigerant and the evaporator in accordance with increasing and decreasing demands, respectively, for refrigeration on the evaporator and increasing and decreasing the contact surface between the condenser and the gaseous refrigerant therein in accordance with increasing and decreasing demand, respectively, for refrigeration on the evaporator.

- ANDREW A. KUCHER. 

